The specific aims of the proposed project are to determine the effects of commonly ingested concentrations of ethanol on growth and differentiation of rat neural cells in culture, both tumor cells and primary cultures, as models for determining the effects of ethanol on fetal development of the nervous system. The cells used will be; (3) primary rat fetal neuronal cells; (4) primary rat fetal mixed glial/neuronal cells. These cultures are known to reproduce, in large part, the events occurring during utero and postnatal brain development. The advantage of using cultures is that we can precisely control conditions of growth, particularly ethanol levels, since it is a close system. Any effects seen in C6 (tumor) cells will be verified with the primary cultures. Effects of ethanol on neurons will be determined using primary cultures. Measures of growth of the cultures will be (1) cell counts; (2) DNA levels; (3) total and soluble protein content; (4) levels of metabolic enzymes. Measures of differentiation will be (1) morphology; (2) S-100 protein levels in glial cultures; (3) neuron-specific enolase (NSE) levels in neuronal cultures: (4) rates of synthesis of S-100 and NSE; (5) levels of mRNA for S-100 and NSE using specific oligonucleotide probes. The cells will be cultured until fully differentiated in the presence of varied physiological levels of ethanol and the above parameters measured at stages of culture. These experiments should answer the questions; (1) Does ethanol retard growth of glial or neurons during development transiently or permanently?; (2) Does ethanol retard differentiation during development transiently or permanently? (3 Are there sensitive periods of development when ethanol exerts major effects on growth or differentiation of the brain. These studies should provide important information on specific effects of ethanol, during fetal development, on specific elements in the nervous system, which may lead to rational strategies of intervention and prevention of the "fetal alcohol syndrome".